can you get a close up of the defects to give a better idea of what's going on?

It's unlikely to be oxidation, Turbine grey is a metallic COB colour, they tend not to oxidise much, if at all. Water spotting/etching can be touch and go if it's safe to remove at all. Magnesium and calcium, both commonly found in tap water as well as rain water, can be very corrosive, so can pit clear pretty heavily.

Don't use Farecla until you have a finer polish to follow up with, and even then it's probably WAY too aggressive for what you need. Deep crystal is a paint cleaner, not a corrective polish, so it won't do anything to remove polisher marring or swirls. The marring will just be really clean...

I spent the day up at killcare today, could have called in on the way though if I'd seen this sooner!

Thanks for the response tinsnips. I did use to have a finishing polish 3M something or other. Tho its gone missing do you suggest any?

ts pretty hard to get a photo and the right lighting when you only have a camera phone, im going to say its water marks and it looks all. Nice. And shiny until you get sun on the right angle then it looks poo. Ill try get a photo when the sun comes up.

for a finishing polish on holden paint (which is on the sticky side) I like meguiars M205 from their pro range or Scholl S30 (the only scholl product I like). Neither are the best for all jobs, but are easy to work with on holden clears. You might even be able to one step it with some Megs D300 if you can get it (I buy it from the UK but there is one supplier here for it apparently) or Meg's ultimate compound (which you can get anywhere - autobarn/supercheap/etc). Ultimate compound is a handy tool, if a bit oily and dusty, for sticky paints. It's not what I reach for when working on euros and hard clears but for the sticky jap paints (holden included) it can come in handy. It has a moderate cut but finishes relatively well if using a DA polisher (not the rockwell rotary you have though) and polishing foam or finishing microfibre pads.

I'd suggest picking up a half decent DA if you want to tackle it yourself. That rockwell rotary is going to throw a heap of heat into the panel and make working it more difficult, as well as binding up and wanting to walk away on you with the sticky paint. Rockwell have a DA for about 80 bucks I think that is apparently not too bad if you can find one with a straight spindle so the backing plate spins true (big time fault). It's apparently noisy as hell and not the smoothest thing, but does have an 8mm orbit and will take good pads, rather than the tie on wool/microfibre junk.

Above that, look at the new concours dual force from www.waxit.com.au - with an 8mm orbit (on sale for about $200 at the moment, I think), or the zentool from www.zas.com.au with a 21mm orbit (about $300). I would say the concours would be the better beginner tool but if you know your way around a polisher the 21mm Zentool will give quicker results. If you were going to use it every day, I'd say go for a Rupes 21, but $700 for a tool you'll only use occasionally is a bit over the top, whereas I'm using mine just about every day. The concours will do everything you need it to and be much more forgiving and safer than a rotary, particularly a rotary without electronic torque control (most lower end rotaries).

Without seeing it, there's no way I can tell you what's going to be the best option to fix it. Sometimes a waterspot remover will shift it if it's just on the surface - most use Acetic acid (try some vinegar - same same), sometimes a stronger phosphoric acid or hydrofluoric acid will shift it, but if it's etched, meaning it's pitted into the clear, it will at the very least need a moderate compound if not more.

If all that sounds too daunting, I have a pro contact up that way that can probably help you out unless you have a reason to come to sydney and I'll take a look at it.

i actually went F##ck it. and actually went to town on it today, and behold it actually came up really well, it does have swirl marks i just took my time working in pretty small areas, now all i need to do it get meguiars M205 you said, but you are right the buff certainly like to go for a walk if you dont keep an eye on it. its actually the first time i have ever buffed it ate all the surface crap off and now its a nice smoooth surface. im going to wash it when the sun goes down and then clay bar it about more as i notiiced it has alot of crap in the paint (lived right next to a train station) then wax it ( for the protection) then when i get some money get the polish. i rang a detailer today they said for a whole package (full day of buffing) around 600 dollars. that's why i decided to do it

i use to detail new cars, its a total different bowl game compared to used cars!!

either should be fine, red foam is my favourite though. If you're using the same rotary to do it, I'd actually go for Scholl S30 over M205 - works with rotary better, i find. Get it from waxit.com.au - they have 250mL bottles for not that much.